Expander ring for combustion engines



1951 .A. J. DAVIS 2,569,601

EXPANDER RING FOR COMBUSTION ENGINES Filed Sept. 19, 1950 mum Ill IIIIUI1 I I I l lll k I 3| I u l FIG! IN V EN TOR.

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Patented Oct. 2, 1 951 ENCIINES' J I Alto L. liens; nigemernmaApplication September 19, 19 50, Serial-No. 1 85-,528=

. 1 'I;his invention relates topistonrings; andrnore part c larly to. ne pander rin for a. ombustion. en neobject of this; invention is toprovide;- an

QXDender-r n for u e with-t e convent na pison ri s. of; a comb stion. nne wh ch i p rt cu ar v' ada ted. t f ectively d reaseen in noises ue tme allic contactin between. the p s g: and the ston-and cylinder.

Another" object. of this invention is to provide an expander ring foruse with the conventional piston rings of' a; combustion engine which isea i ular t dapted to. exe t a uni or force at more points along thepiston. ring to, thereby form an efiegtivessal betwee hslatte and thecylinder wall.

Afurther object of this invention is to, proyide an x and r r n forusewi hvent n s of? q mhust on. en ine whi h. is parti arly adapte to.exert a uniform force at a l po a one the. o l in to. ther b insu re aiv uniform removal of the excess oil from the cylinder wall.

A still further object of this invention is to provide an expander ringfor combustion engines which is relatively simple in structure and cheapto manufacture.

The above and still further objects and advantages of the invention willbecome apparent upon consideration of the followed detailed descriptionof the invention, when taken in conjunction with the accompanyingdrawing, where- 1n:

Figure 1 is an elevational view, with parts broken away and in section,showing the expander ring of the present invention supported in the ringgrooves of a piston intermediate the bottom faces of the grooves and thepiston rings;

Figure 2 is an enlarged fragmentary sectional view taken along the line2-2 of Figure 1;

Figure 3 is a perspective view of the expander ring of the presentinvention, shown broken away intermediate its ends;

Figure 4 is a sectional view taken along the line 4-4 of Figure 3; and

Figure 5 is an enlarged fragmentary sectional view showing an expanderring supported. in the ring grooves of a piston intermediate the bottomface of the groove and a piston ring.

Referring now more particularly to the drawings, wherein like referencenumerals have been used throughout the several views to designate likeparts, there is shown the expander ring of the present invention,generally designated by the reference numeral Ill supported in thegrooves I l,

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resend; l,3 of; they piston I45. As clearly shown in Figure 5, theexpander ring Ill is supported intermediate thebottomwall I5 of the ringgroove and; the adjacent one of the piston rings 16;. In Figure 1, thereisshown a solid compression ring I! supported; withirr the slot I3 and;ventilated oilrings l8 and I9 supported within the grooves Extendingtransversely of the piston M are; a plurality of spaced; oil drainage.ports, generally; designated; by the reference numerals 20. Each of; theoil drainage ports has one end in communication with, the. interior ofthe piston l4,

and has its other end in communication with the groove H. Accordingly,upon moving the rings l6, over the bounding wall of the cylinder, notshow c nside ab e. 1 P s u e i i t up ahead o h in This essu builds p osuch a exten hat; oil as es t e y rntac in f; e the r ng:- nd he.pressure. is n dd ly relieved as; the slot moves overthe oil, so tthe.cunt-ace tension of the oil; causes a wave of oil to rise up into theslots. Thus, excessive oil is removed from the cylinder. Theaforementioned piston and piston ring structure is conventional andforms no part of the present invention. It is to be noted, however, thatto effectively decrease engine noises, it is desirable to eliminate themetallic contact between the piston ring l6 and the bottom walls I 5 ofthe piston grooves ll, l2 and I3. Furthermore, it is desirable to exertthe uniform force at all points along the piston ring Hi, to therebyform an effective seal between the latter and the cylinder wall and toeffect a relatively uniform removal of excess oil from the cylinderwall.

Accordingly, the expander rings of the present invention are supportedin each of the ring grooves ll, l2 and I3, as previously described. Theexpander rings are fabricated of a resilient, rubber-containingmaterial, adapted to withstand the normal operating temperatures foundin the cylinders of combustion engines. The expander ring I0 embodies anelongated body 2| which includes a pair of bars 22 and 23 havingrectangular cross sections disposed in superimposed spaced relation withrespect to each other. Extending between the bars 22 and 23 at spacedintervals therealong are the connecting links, generally designated bythe reference numeral 24. Each of the connecting links is rectangular incross-section and has one end secured to the bar 22 and has the otherend secured to the bar 23. As clearly shown in Figure 4, one face of theconnecting links 24 is disposed in coplanar relation with respect to theadjacent side face of the bars 22 and 23, while the other face thereof,designated by the reference numeral 25, terminates adjacent to andspaced from the opposite side face of said bars.

In actual use, the expander rings III are inserted within the ringgrooves II with the coplanar side faces of the bars 22 and 23 and theconnecting links 24 abuttin against the bottom walls l5 of the grooves.The piston rings, namely, the oil rings [8 and I9 and the compressionring H are then circumposed about the expander rings. It is to be notedthat the disposition of the side faces 25 of the connecting links 24with respect to the adjacent side faces of the bars 22 and 23 permit theportions of the bars 22 and 23 which project beyond the aforementionedside faces to be slightly compressed. Accordingly, in the event that theexpander rings are slightly larger than desirable, a clearance will beprovided intermediate the extended portions of the bars which permitsthe expander ring to be slightly compressed.

When assembled within the groove I 3, the expander ring In exerts auniform pressure against the inner periphery of the compression ring l1.Similarly, the expander rings disposed within the grooves II and I2exert a uniform pressure against the ventilated oil rings I8 and IS. Thespacing intermediate the connecting links 24 permits the excess oil toflow inwardly from the cylinder wall through the ventilated oil ring I8into the bore 20, and thence into the interior of the piston.

The ring should preferably be of one of the well known oil-resistant,resilient compositions, such as neoprene (polymerized chlorobutadiene)or one of the oil-resistant, resilient copolymers of butadiene with aminor proportion of acrylonitrile, which are available commerciallyunder such trade names as Hycar and Paracril. These oil-resistantrubbers have the property of resist- 4 ing change under high temperatureservice somewhat better than natural rubber, which is especiallydesirable in this type of service.

Although only one embodiment of the expander ring of the presentinvention has been described, it is readily apparent that numerousmodifications can be made without departing from the spirit of theinvention as set forth in the appended claim.

What I claim is:

An expander ring for support in the ring groove I of a pistonintermediate the bottom face of said groove and a piston ring comprisingan elongated body fabricated of resilient material and including a pairof bars having rectangular crosssections disposed in superimposed spacedrelation with respect to each other, and means disposed intermediatesaid bars at spaced intervals therealong for securing said bars togetherand forming therebetween a plurality of longitudinally spaced groovesfor the passage therethrough of oil, said means comprising connectinglinks having rectangular cross-sections and each having its ends securedto said bars. and each of said connecting links having one side facearranged in coplanar relation with respect to one side face of said barsand havin the other side face thereof terminating adjacent to and spacedfrom the opposite side face of said bars.

ALTO J. DAVIS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,723,432 Morton Aug. 6, 19292,078,519 Wilkening Apr. 27, 1937 2,369,263 Teetor Feb. 13, 19452,465,521 Marien Mar. 29, 1949

